39. Fortunately, the demonstration _____ to be quite peaceful.
　A. turned in　　B. turned out　　C. showed off　　D. showed up
答案：B。turn out：原来是，最后证明是。The weather turned out to be fine.结果天气很好。turn in：交换，交上。You must turn in your uniform before you leave. 你离开前必须把制服交还。show off：炫耀，卖弄。show off one’s knowledge 炫耀知识。show up：变的突出，显得醒目。White turns up well against a blue background.白色经蓝色的背景一衬托更为醒目。

40. _____ was unimportant.
　A. Whether he enjoyed our dinner or not      B. No matter how he enjoyed our dinner
　C. If he enjoyed our dinner                  D. What he enjoyed our dinner
答案：A。本句为主语从句，意思是“他是否喜欢我们的饭不重要。”只有A最符合题意。

41. Selfish people often take _____ of other people’s kindness.
　A. advantage　　B. care　　C. use　　D. profit
答案：A。take advantage of：利用。本句的意思是“自私的人都利用他的善良”，所以A最符合题意。take care of：照顾。其余两个词都没有这样的搭配。

42. His business is growing so fast that he must _____ more workers.
　A. take up　　B. take on　　C. take over　　D. take out
答案：B。take on：有“开始雇佣”的意思。如：Doctor Watson isn’t taking on any new patients.沃森医生不再接收新病人了。本句的意思是“他的生意发展的如此的快，他必须雇佣更多的工人。”因此B 最符合题意。take up：占去（地方、时间、经历、注意力等）This table takes up too much space.这张桌子太占地方了。take over：接收，接管。The new department head took over yesterday.新的部主任昨天接任。take out：拿出，取出。He took his pen out and signed on the spot.他掏出笔，当场签了字。

43. It is desirable that he _____.
A. gives up trying　　B. give up trying　　C. would give up trying
D. is going to give up trying
答案：B。句型It is desirable （suggested，necessary，requested，ordered，proposed，important）+that+主语+should（可省略）+V（动词原形）。因此本句选B。如：It is strange that he（should）go himself.真奇怪，他怎么自己独自去呢？

44. Young _____ he is, he knows what is the right thing to do.
　A. that　　B. as　　C. although　　D. however
答案：B。as引导的让步状语从句要倒装。可以有以下几种情况：adj+as+主语+系动词be：Young as he is, he knows a lot of things.虽然他年龄不大，可知道的事情很多。n（不带冠词）+as+主语+系动词be：King as he is, he is unhappy.虽然他是个国王，可是他并不快乐。adv+as+主语+动词：Much as I like it, I won’t buy it虽然我很喜欢它，但是我还是不买它。V+as+主语+助动词：Try as she does, she will never pass it.无论她怎样努力，她也不会通过的。

45. This is one of the best books _____ on the subject.
　A. that have ever been written            　　B. which have ever been written
　C. that has ever been written            　　D. whatever have been written
答案：A。因为先行词是复数，而且有形容词的最高级修饰，所以只能选that。